1. Technical Field
The present invention relates to a light scan device and an image display device. Particularly, it relates to a technique for a light scan device for causing a laser light modulated according to an image signal to scan thereby to display an image.
2. Related Art
In recent years, a laser projector by which an image is displayed by forcing a laser light to scan has been proposed as an image display device for displaying an image. Laser light is characterized by its high monochromaticity and directivity. Therefore, a laser projector has an advantage such that an image can be obtained with a good color reproducibility. A technique for an image display device to display an image by forcing a laser light to scan has been proposed by e.g. JP-A-1-245780.
Typically, a laser light is shaped so that the form of a spot formed in an illumination-target region of a screen or the like is substantially circular. In this case, performing the modulation of the laser light at a timing when the center of the spot is incident on a pixel region will cause the laser light for display by a pixel to enter another pixel region neighboring the first pixel. Then, the occurrence of an event such that an image is blurred by modulated light incident on a location different from a location specified by the address information that an image signal carries, i.e. so-called crosstalk, makes it difficult to display an image with a high resolution owing to the unclear outline of the image, etc. To reduce such trouble, it can be considered that a laser light is turned on only in the situation where a whole laser light spot falls in a pixel region. However, in the case where the spot has a circular form with a size comparable to that of the pixel, the lighting time of the laser light for display by the pixel is shortened considerably, which leads to a dark image. To extend the lighting time of laser light, it is conceivable to make the circular spot smaller in comparison to one pixel in size. However, in this case, the gap between scanning lines along which the laser light is made to scan becomes more conspicuous, which makes it difficult to offer a seamless image. As described above, in the art there has been a problem such that it is difficult to display a bright image with high quality.